The BIAS (Baltic Sea Information on the Acoustic Soundscape) project mapped the underwater soundscape in the Baltic Sea. Species-specific temporal and spatial noise pollution limits have not yet been established, and thus work will continue under the programme of measures 2022–2027 through the measure “Restricting underwater noise in certain areas and/or at certain times (TPO2022-MELU1)”.
Underwater construction sometimes causes extraordinarily strong, albeit temporary, local noise in the marine area. Such impulsive noise has been shown to cause behavioural changes, physiological stress, physical damage and even mortality to, for example, fish and marine mammals. Moreover, the upcoming, increasing wind power construction is one of the major sources of impulsive noise, and it is therefore necessary to develop further actions to reduce impulsive noise. The two ongoing international research projects will chart the intensity, distribution, and impact of noise in the Baltic Sea.
The measure consists of the following actions:
1) Research information about the effects of impulsive noise will be put together.
2) Construction, blasting, and dredging activities causing impulsive noise are collected in a national register (e.g. HERTTA) where the source, intensity and time are registered. The register facilitates noise monitoring and specifies information on the level of noise in the marine areas.
3) Existing instructions for building of marine wind farms will be reviewed. Where appropriate, the instructions and recommended practises for e.g. a protection zone from which the animals are expelled, the duration of noise and the timing of the measures will be updated. Technical applications for noise reduction will also be introduced to reduce the effects of impulsive noise during construction.
Study on the use of the register 2016–2018
Preparation of guidelines 2019–2021
Ministry of the Environment